Enforce the 'requirements' field in manifests.

chrome/browser/extensions/updater/extension_downloader_delegate.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_DOWNLOADER_DELEGATE_H_
 #define CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_DOWNLOADER_DELEGATE_H_
 #pragma once
 
 #include <string>
 
@@ skipping 54 matching lines @@
                                          Error error,
                                          const PingResult& ping_result);
 
   // Invoked if the extension had an update available and its crx was
   // successfully downloaded to |path|. Ownership of that file is transferred
   // to the delegate.
   virtual void OnExtensionDownloadFinished(const std::string& id,
                                            const FilePath& path,
                                            const GURL& download_url,
                                            const std::string& version,
-                                           const PingResult& ping_result) = 0;
+                                           const PingResult& ping_result,
+                                           const bool is_sync) = 0;
 
   // Same as OnExtensionDownloadFinished() but only for the kBlacklistAppID
   // extension, which passes different data to the delegate.
   virtual void OnBlacklistDownloadFinished(const std::string& data,
                                            const std::string& package_hash,
                                            const std::string& version,
                                            const PingResult& ping_result) = 0;
 
   // The remaining methods are used by the ExtensionDownloader to retrieve
   // information about extensions from the delegate.
@@ skipping 14 matching lines @@
 
   // Invoked to get the current version of extension |id|. Returns false if
   // that extension is not installed.
   virtual bool GetExtensionExistingVersion(const std::string& id,
                                            std::string* version) = 0;
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_DOWNLOADER_DELEGATE_H_